The present invention relates to an inner operating device for a door lock and, more particularly, to an inner operating device mounted to an inner side of a door for moving a latch between a latching position and an unlatching position.
A type of door lock (so-called panic exit door lock) is mounted to a passageway door or a panic exit door. The panic exit door lock includes an outer operating device mounted to an outer side of a door and an inner operating device mounted to an inner side of the door. The inner operating device is generally of a type different from the outer operating device. The panic exit door device further includes a latch device including a latch movable between a latching position outside of the door and an unlatching position retracted into the door. The door lock can be set to be in a locked state or an unlocked state through an outer cylinder of the outer operating device or an inner cylinder of the inner operating device.
If the door lock is set to be in the unlocked state, the latch can be moved from the latching position to the unlatching position by operating either of the outer operating device and the inner operating device, thereby opening the door. If the door lock is set to be in the locked state, the latch cannot be moved from the latching position to the unlatching position when the outer operating device is operated, avoiding opening of the door by operating the outer operating device. This prevents a burglar from intruding from the outer side of the door into the inner side of the door. However, for emergency exit, the panic exit door lock must permit a user to easily use the inner operating device to move the latch from the latching position to the unlatching position no matter in the locked or unlocked state. Namely, the door has to be easily opened from the inside no matter the door lock is in the locked or unlocked state.
Since the panic exit door lock is so set that the inner operating device can be operated to open the door no matter in the locked or unlocked state, in a case that the user is at the inner side of the door while the panic exit door lock is set to be in the locked state, the user cannot confirm whether the panic exit door lock is actually in the locked state by operating the inner operating device, resulting in inconvenience in use. Furthermore, the inner operating device of the panic exit door lock has a complicated mechanical structure and, thus, has high manufacturing costs.